The dbm database-map
type, which is really the ndbm form of database,
is the traditional form of Unix database file. Data is stored in one
file, keys in another. The data must fit in blocks of fixed sizes, so
there is usually a limit on the maximum size (1 kilobyte or so) on
any given stored piece of data. The dbm
database-map type is available only if sendmail
was compiled with NDBM declared (NDBM).
Many database switches are available with this dbm
database-map type. All are listed in Table 23-9.
Table 23-9. The dbm database-map type K command switches
|
-A
|
-A
|
Append values for duplicate keys
|
|
-a
|
-a
|
Append tag on successful match
|
|
-D
|
-D
|
Don't use this database map if DeliveryMode=defer
|
|
-f
|
-f
|
Don't fold keys to lowercase
|
|
-m
|
-m
|
Suppress replacement on match
|
|
-N
|
-N
|
Append a null byte to all keys
|
|
-O
|
-O
|
Never add a null byte
|
|
-o
|
-o
|
The database file is optional
|
|
-q
|
-q
|
Don't strip quotes from key
|
|
-S
|
-S
|
Space replacement character
|
|
-T
|
-T
|
Suffix to append on temporary failure
|
|
-t
|
-t
|
Ignore temporary errors
|
This is the database-map type used with aliases
files, if the hash type is unavailable. This type
is also needed on machines that employ NIS because the underlying
files for those services are stored in dbm format.
Note that because of the implicit limit on the size of a piece of
data, you should consider using one of the db(3)
hash or btree types instead.
